package com.atguigu.facade;

/**
 * @program: design-patterns
 * @author: yangshen
 * @description: 子系统3：投影仪
 * @create: 2022-02-21 14:35
 **/
public class Projector {
    /**
     * 单例模式，使用饿汉式
     */
    private static Projector instance = new Projector();

    public static Projector getInstance(){
        return instance;
    }

    public void on(){
        System.out.println("投影仪 打开");
    }

    public void off(){
        System.out.println("投影仪 关闭");
    }

    public void focus(){
        System.out.println("投影仪 正在投影");
    }

}
